# 225 grams of NH_4NO_3 in 2.5 liters of water has what concentration?

$\text{Concentration"="Moles of solute"/"Volume of solution}$
$\text{Concentration}$ $=$ $\frac{225 \cdot \cancel{g}}{80.04 \cdot \cancel{g} \cdot m o {l}^{-} 1} \times \frac{1}{2.5 \cdot L}$ $\cong$ $1.1 \cdot m o l \cdot {L}^{-} 1$.